A monitoring core without any check plugins for your hosts and services would be nothing. While there is a huge collection of plugins available on the net, the original Nagios plugins are still compatible with Icinga 1.x and Icinga 2.x
Our friends at the Nagios plugins development team have now released 1.5 containing numerous bug-fixes as well as new features. Please also note the dash in their updated domain: “nagios–plugins.org”. Furthermore they have moved their code and issue tracker to github recently so make sure to update your bookmarks! :)
Thanks for your effort guys, much appreciated!